CVE-2026-121197 in Chrome
Summary
by MITRE • 11/03/2026
Out of bounds read in ANGLE in Google Chrome on on Mac prior to 157.0.8103.38 allowed a remote attacker to read memory outside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified as an out-of-bounds read within the ANGLE graphics library in Google Chrome represents a critical memory safety flaw that compromises the integrity of the browser's execution environment on macOS systems prior to version 157.0.8103.38. This issue stems from improper boundary checks during the processing of graphical data, allowing an attacker who crafts a malicious HTML page containing specific WebGL or canvas operations to trigger a read operation that accesses memory locations beyond the intended buffer limits. The ANGLE library serves as the translation layer between web graphics APIs like OpenGL ES and the underlying native platform graphics API, such as Metal on macOS, making it a central component in rendering complex visual content for modern web applications.
From a technical perspective, this flaw is classified under CWE-125, which denotes Out-of-bounds Read vulnerabilities. The root cause lies in the failure of the ANGLE implementation to correctly validate array indices or buffer sizes before performing memory access operations. When a remote attacker hosts a crafted HTML page and lures a victim into visiting it, the browser's rendering engine processes the malicious graphics commands. Due to the missing validation logic, the application reads from adjacent memory regions that are not part of the allocated object. This behavior violates the principle of least privilege by exposing internal data structures or sensitive information stored in nearby memory blocks to the attacker-controlled context.
The operational impact of this vulnerability is significant because it facilitates a sandbox escape scenario on macOS. Google Chrome employs a multi-process architecture with strict sandboxes designed to isolate web content from the host operating system and other processes. By exploiting an out-of-bounds read, an attacker can potentially leak sensitive information such as cryptographic keys, session tokens, or internal browser state data that resides in memory adjacent to the vulnerable buffer. While this specific vulnerability is primarily characterized by a read operation rather than arbitrary code execution, the leakage of privileged memory contents can be leveraged for further exploitation chains, including bypassing security mitigations like ASLR or stealing authentication credentials stored within the browser's secure storage mechanisms.
This incident aligns with ATT&CK technique T1005, which refers to Data from Local System, specifically focusing on application data harvesting through memory reads. The ability to read arbitrary memory locations outside of sandboxed boundaries undermines the foundational security model of modern web browsers. It demonstrates how graphical processing components can become vectors for information disclosure if boundary conditions are not rigorously enforced during runtime execution.
To mitigate this risk, organizations and individual users must ensure that Google Chrome is updated to version 157.0.8103.38 or later on macOS platforms. This update contains the necessary patches that enforce strict bounds checking within the ANGLE library's memory access routines. Additionally, security teams should monitor for indicators of compromise related to unusual memory allocation patterns in browser processes and consider deploying content security policies that restrict the execution of untrusted scripts from unknown origins. Regular patch management cycles are essential to address such high-severity vulnerabilities promptly, as they directly impact the confidentiality and integrity of user data processed by the web browser.